John e



(No Model.)

J. R. BACK.

FRoNT APRON POB. LATHE GARRIAGBS. No. 388,808. Patented Sept. 4, 1888.

.IVE y l 1 8 y l Wiiiii Y l t .t mail l 1 @t l i .1| p5: -l ,1 u||| |||||it t e mwlllllnmuummmmnmhilll ai eeeeeee @DH1/weeen.

PUERSv Phono-Lnmlupmr. washington. D C

UNITED STATES JOIIN lt. Afl/K, 0F WORCESTER, MASS T() FREDERICK E. RE

FRONT APRON FOR PATENT OFFICEA LATHE-CARRIAG ES.

SPECIFICATION forming part of Letters Patent No. 388,808, dated September 4, 1888.

Application filed May 14, 11288.

To aZZ whom it 11mg/ concern.-

Be it known that I, JOHN R. BACK, a citizen of the United States, residing at \Vorcester, in the county of Worcester and State of Massachusetts, have invented a new and useful Improvement in Metal-Turning Lathes, Set forth in the annexed specification, which, to gcthcr with accompanying drawings, forming a part of the same, contains a full, clear, and exact description of my invention.

My invention relates to certain improvements in the part of a metal-turning lathe known as the apron, and it consists in the features herei naftcr described, and pointed out in the claim.

Figure l represents in sectional view a portion ofan apron of a lathe, (shown on line X X, Fig. 2,) together with such part of the coutiguous portion of the lathe as will aid in illustrating thc nature of my invention. Fig. 2 is a rear view of the casting forming the framework of the apron; and Fig. 3 is a top view of thesame, both Fig. 2 and Fig. 3, showing the casting as detached from the connected portions of the lathe.

Similar letters refer to similar parts in the several views.

A denotes a portion of the bed of a metalturniug lathe, and ll one of the ways along which the tool-supporting carriage is moved lengthwise the bed of the lathe in the operation of' turning.

(l is a portion of the carriage, to the under side of which is attached the plate I), known as the apron and supporting suitable moellanism between it and the bed of the lathe for effecting the longitudinal or feeding motion of the carriage C along thc ways of the lathe.

The mechanism supported by the apron for causing the feeding motion of the carriage varies in different makes of lathes; but it is usual to place a rack, E, attached to the overhanging portieri of the lathe-bed, and the trav ersing motion of the carriage is accomplished by means of a rotating pinion, F', turning in a bearing in the frame-work of the apron and engaging the rack E.

Serial No. 273,905. (No model.)

In the construction shown in the accompanying drawings, F denotes a sliding spindle having a pinion, F, formed on one end and a milled knob, F2, at the other or outer end to allow the spindle to be moved lengthwise in its bearings, and the pinion F to be engaged or disengaged from the rack E. totating bctween the bearings G and ll and having a spline-connection with the spindle F is a gearwheel, J, to which rotary motion is imparted through the eranklever K, having a pinion engaging the gear J, but not shown in the drawings, except as it isindicated by thebroken line a, Fig. 2, the gear J being indicated in the drawings by the broken line b. Motion is also communicated in the usual and wellknown manner to the pinion by means of the fccd-rod and leadscrew, whose relative positions are shown at L and M, Fig. 1, through intermediate actuating mechanism which is common in metal-tnrnii'lglathes; butas it forms no partof my present invention it is not herein shown or described. However rotary motion may be communicated to the spindle F and pinion F,the entire strain incident to traversing the carriage along the ways of the lathe is borne by the spindle F and pinion F, and it is important that a substantial and rigid support be given to the spindle F in the sup` porting-apron. I accomplish this result by forming the two bearings G and ll in a single casting, making the plate D and thc plate N integral and united by the flange N', through which screws are placed in the screw-holes c c, joining the apron to the remaining parts of the carriage. The plate N is also united to the plate D by means of the end flange, N2, the two plates l) and N being thus maintained iu a parallel position and rigidly held against any strain upon the spindle F. rlhe two bearings G and H are also easily made in true alignment with each other, and the go spindle held in place so it may be rotated or slid in its bearings without undue friction. The expense of constructing the apron is very much reduced, as both bearings can be bored and rcamed at one operation and their alignment thus rendered certain.

Vvhat I claim as niy invention, and desire to secure by Letters Patent, is

In the apron 0f e metal-turning lathe carry ing a rotating spindle, having :i pinion engagging :L fixed mek on the bed of the lathe, whereby the feeding motion of the t00l-cz1rriage is effected, the spindle supporting frame con` ings G and II, substantially as described.

JOHN R. BACK. \Vil.nesses:

F. E. REED, RUFUS B. FOWLER. 

